Anytime something out of the ordinary happens to an AFCS, it should be reported!!!
Tell the folks who don't report things officially, but tell you after over a pint that how would they like it if a really serious problem didn't get report and was still present when they got the aircraft?
In fact, any time something out of the ordinary happens to a system it should be reported somewhere, somehow. A Bell 212 crashed with a total electrical failure (which is not supposed to ever be able to happen to it) and it was discovered that not only had that airframe had a total electrical failure a year before, but there was at least one other airframe that had a similar problem - neither got reported. 7 dead.